Microfiber chalkboard eraser

ABSTRACT

The microfiber chalkboard eraser has a central core fully covered by a microfiber cleaning sheet with a finger holder cap covered on its top. The microfiber cleaning sheet cleans the chalkboard cleaner and reduces the air borne chalk dust compared to commonly used chalkboard erasers. The microfiber cleaning sheet has two sides that can be configured to form four cleaning surfaces, and can be washed or replaced when the two sides are soiled with chalk dust. Additionally, the finger holder cap can keep a user&#39;s hands free from chalk dust.

FIELD OF THE INVENTION

The present invention relates generally to chalkboard and marker board erasers, and specifically to a chalkboard and marker board eraser using microfiber material as a cleaning material.

BACKGROUND OF THE INVENTION

Blackboard erasers are a common item of everyday life. There are few among us who, as elementary school students, have not undertaken the chores of assisting a teacher in cleaning a blackboard or cleaning blackboard erasers by banging them together in the school yard. As such, many of us remember problems attendant with using the common blackboard eraser.

The common blackboard eraser typically is made from laminated felt pads attached to a cardboard backing board, and with its use, three problems arise. The first is the chalk dust. The felt pads are normally made of nylon threads that do not hold much chalk dust, thereby chalk dust is released into the classrooms with use. A second problem is the construction of the eraser. The felt pads and backing used to secure the felt pads are often too thin causing a user to hold the eraser by the sides of the felt pads in order to clean a blackboard. Therefore, the user often gets chalk dust on his or her fingers just from using the eraser. The third problem is that of ghosts. Common chalkboard erasers do not clean the chalkboard sufficiently; a significant quantity of chalk dust remains after using the common eraser, and the common eraser does not completely erase the writing but often leaves a significant image of the erased writing (a ghost image) that may interfere with new writing.

Several improvements have been made to overcome the problem of chalk dust. Many of the improvements have taken the form of adding mechanical brushes or rollers to the eraser, or by adding bins or other devices to collect the dust. See U.S. Pat. No. 6,895,627 to Lin, U.S. Pat. No. 4,941,225 to Liao, U.S. Pat. No. 4,742,594 to Chen, U.S. Pat. No. 4,392,268 to Victor, and U.S. Pat. No. 4,080,683 to Chong. Other improvements have been made to overcome the problem of an eraser easier to use, the improvements included adding holders, handles, straps, and backing plates. See U.S. Pat. No. 5,365,631 to Emerick, U.S. Pat. No. 5,072,483 to Durand, and U.S. Pat. No. 4,543,680 to Vlahos. Still other improvements made to erasers for whiteboards include providing disposable cleaning surfaces. See U.S. Pat. No. 4,937,910 to Frazier and U.S. Application 2004/0205919 by Sims.

The common blackboard eraser comprises laminated felt pads made mostly of nylon threads. Other cleaning materials such as chamois and sponge can erase the blackboard cleaner than felt, but each alternate material has at least one disadvantage. Sponge has a short life expectancy, and the cleaning efficiency of chamois decreases rapidly with use and chamois is difficult to clean.

However, none of these improvements were widely adopted. The eraser of yesterday is the eraser of today.

SUMMARY OF THE INVENTION

In accordance with the invention, a microfiber chalkboard eraser is provided for use with chalkboards, marker boards, and other writing surfaces, wherein the erasing surface is a microfiber material. The microfiber chalkboard eraser comprises a rectangular central core of a resilient material, a microfiber cleaning sheet covering the central core, and a cap or holder securing the covering and the resilient core.

Objects of the invention are to provide a microfiber chalkboard eraser that can more completely clean the chalkboard, that can hold more chalk dust, that can remove chalk dust easier and faster, and that can clean the chalkboard more efficiently than the common chalkboard eraser.

Other objects of the invention include providing an easily replaceable cleaning surface that can be reused after being cleaned, and providing an eraser that has a finger cap or holder to keep the user's fingers free from chalk dust.

The foregoing and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a unit of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention.

In the drawings:

FIG. 1 is a perspective view of a microfiber chalkboard eraser according to the present invention,

FIG. 2 is a view in perspective of the eraser of FIG. 1 before assembling without the finger holder cap;

FIG. 3 is a view in perspective of the eraser of FIG. 1 in partially assembled condition without the finger holder cap;

FIG. 4 is a plan view of the cleaning sheet;

FIG. 5 is a perspective view of the central core 11 in a first state of assembly, wherein the cleaning sheet 13 has been reversed;

FIG. 6 is a perspective view of another embodiment of the eraser of FIG. 1 in which the top surface is not covered;

FIG. 7 is a perspective view of still another embodiment of the eraser of FIG. 1 in which only the bottom surface of the central core is covered; and

FIG. 8 is a perspective view of yet another embodiment of the eraser of FIG. 1 in which the front surface, the back surface, the bottom surface, and the top surface of the central core are covered.

DETAILED DESCRIPTION OF THE INVENTION

Referring now to FIGS. 1 through 4, a first embodiment of the microfiber chalkboard eraser 10 is shown which includes a central core 11 (shown on FIG. 2), a finger cap or holder 12, and a microfiber fabric cleaning sheet 13. More specifically, the holder 12 has a rectangular shape with an open bottom (not shown). The holder 12 has a height sufficient to keep the user's fingers from the cleaning sheet 13 thereby avoiding chalk dust. The holder 12 may be made of plastic or other suitable materials. The central core 11 has a rectangular form and sized to fit within the holder 12, and in some aspects, retain the microfiber fabric cleaning sheet 13 on the central core 11 when the covered central core 11 is placed within the holder 12. The central core 11 preferrably may be made from of EPS (Expanded Polystyrene) foam or EPP (Expanded Polypropylene) foam.

The central core 11 is covered by the microfiber cleaning sheet 13. Microfibers are small fibers having a dimension of about 0.01 to about 5 denier, typically about 0.1 to about 1.0 denier. Denier is a scale for the heaviness (largely related to thickness) of fibers in a fabric. The higher the denier, the thicker the fiber. The denier value is defined as the mass in grams per 9000 meters of yarn. Microfibers are typically made from two relatively incompatible polymer materials, for example, polyester and polyamide in a weight percentage ratio ranging from about 50/50 to about 90/10. The fibers are spun extruded and then split into microfilaments during manufacturing. The most common structure of the microfiber is a core structure with wedge shaped perimeter structures. The yarn made from the microfiber contains high surface area wedge shaped filaments and a core filament with furrows and channels. These furrows and channels help provide a capillary action, which draws the dust including chalk dust into the void spaces resulting in microfiber fabrics having much higher capacity of holding chalk dust than traditional cleaning material like nylon threads, sponge, and chamois. Since there can be about 180,000 microfibers per square inch, the soft fabric has a large surface area available for contact with chalk dust, thereby removing more chalk and chalk dust from blackboards than commonly used chalkboard erasers.

FIG. 2 shows the central core 11 in a first state of being covered by cleaning sheet 13. FIG. 3 show the central core 11 in a second state of being covered by the cleaning sheet 13.

Referring now to FIG. 4, the microfiber cleaning sheet 13 has panels connected along fold lines. Each panel of the microfiber cleaning sheet 13 has two sides; the side adjacent to the central core 11 is the front side of this panel, and the opposite side is the back side. The microfiber cleaning sheet 13 includes a first side cover panel 30, a top cover panel 32, a second side cover panel 34, a bottom cover panel 36, and a third side cover panel 38. The bottom cover panel 36 is connected to the first side cover panel 30 at fold line 35, and the third side cover panel 38 at fold line 37. The top cover panel 32 is connected to the first side cover panel 30 at fold line 31 and to the second side cover panel 34 at fold line 33.

A first end cover panel 40 and a second end cover panel 44 are connected to the bottom cover panel 36 and the top cover panel 32 respectively at fold line 39 and 43. A third end cover panel 42 and a fourth end cover panel 46 are connected to the bottom cover panel 36 and the top cover panel 32 respectively at fold line 41 and 45.

The dimensions of the microfiber cleaning sheet 13 are such that when folded along the fold lines 31, 33, 35, 37, 39, 41, 43 and 45, the microfiber cleaning sheet 13 completely covers the central core 11. The microfiber cleaning sheet 13 may be secured using any convenient means, including hook and loop fasteners as shown in FIGS. 2 through 4. For example, loop strip 48 is attached to one edge of the back side of the second side cover panel 34, and loop strips 50 are attached to one edge each of the back side of the second and fourth end cover panels 44 and 46. Hook strip 47 (shown on FIG. 3) is attached to one edge of the front side of the third side cover panel 38 in a position to mate with loop strap 48 when the microfiber cleaning sheet 13 is folded to cover the central core 11. Likewise, hook strips 49 (shown on FIG. 3) are attached to one edge each of the front side of the first and third side cover panels 40 and 42.

The central core 11 is fully covered by the microfiber cleaning sheet 13 all side sides when the panel 34 is attached to the panel 38 and the panel 44 is attached to the panel 40 and the panel 46 is attached to the panel 42. The microfiber chalkboard eraser 10 is assembled when the central core fully covered by the microfiber cleaning sheet 13 is fitted in the holder 12 with panel 36 as the cleaning surface.

FIG. 5 shows a perspective view of the central core 11 in a first state of assembly, wherein the cleaning sheet 13 has been reversed so that the back side of the cleaning sheet 13 is placed adjacent to the central core 11. When the cleaning surface or the back side of bottom cover panel 36 is soiled with chalk dust, the covered central core 11 can be removed from the holder 12, and the covered central core 11 can be repositioned so that the back side of the top cover panel 32 is the cleaning surface. The covered central core is then reinserted into the holder 12. When the top cover panel is soiled, the covered central core can be removed from the holder 12, the cleaning sheet 13 removed from the central core 11, and reversed as shown in FIG. 5 so that the clean front side now faces outward. The cleaning sheet 13 may be replaced on the central core 11 and reinserted into the holder 12. In this manner, the cleaning sheet 13 has four surfaces with which to clean a blackboard; the front side of the top cover panel, the back side of the top cover panel, the front side of the bottom cover panel, and the back side of the bottom cover panel. When all four surfaces are soiled, the cleaning sheet 13 may be washed or replaced.

A second embodiment of the present invention is shown is FIG. 6, wherein the microfiber cleaning sheet comprises a bottom cover panel 36, a first side cover panel 30, a third side cover panel 38, a first end cover panel 40, and a third end cover panel 42. Panels 30, 38, 40, and 42 are attached to the central core 11 using any convenient means such as hook and loop fasteners (not shown). The third embodiment is shown without holder 12, but holder 12 may be used.

FIG. 7 shows a third embodiment of the present invention in which the microfiber cleaning sheet 13 comprises only a bottom cover panel 36 attached to the bottom surface of the central core 11 by means like hook and loop fasteners. Also the finger holder cap 12 of the first embodiment optionally may be used.

A fourth embodiment is shown in FIG. 8, wherein the cleaning sheet 13 comprises a top cover panel, a bottom cover panel, a first side cover panel, a second side cover panel, and a third cover panel. A loop strip 48 is attached to one edge of the front side of the second side cover panel 34 corresponding to a loop strip (not shown) attached to the back side of one edge of the third side cover panel 38. When the cleaning sheet 13 is assembled to cover the central core 11, the ends of the central core 11 are uncovered. Preferably, holder 12 of the first embodiment secures the cleaning sheet 13 and the central core 11.

As the present invention may be embodied in several forms without departing from the spirit or essential characteristics thereof, it should also be understood that the above-described embodiments are not limited by any of the details of the foregoing description, unless otherwise specified, but rather should be construed broadly within its spirit and scope as defined in the appended claims, and therefore all changes and modifications that fall within the metes and bounds of the claims, or equivalence of such metes and bounds are therefore intended to be embraced by the appended claims. 

1. An eraser for cleaning blackboards and whiteboards comprising: a central core; and a cleaning sheet, wherein the cleaning sheet is removeably affixed to the central core.
 2. The eraser of claim 1 further comprising a holder, wherein the holder is removeably affixed to the central core.
 3. The eraser of claim 1, wherein the central core is comprised of a resilient material.
 4. The eraser of claim 3, wherein the resilient material is expanded polystyrene foam.
 5. The eraser of claim 4, wherein the resilient material is expanded polypropylene foam.
 6. The eraser of claim 1, wherein the central core is a rectangular prism having a top face, a bottom face, a first end face, a second end face, a front face, and a back face.
 7. The eraser of claim 6, wherein the cleaning sheet is a microfiber material.
 8. The eraser of claim 6, wherein the cleaning sheet is reversible.
 9. The eraser of claim 7, wherein the cleaning sheet is removeably affixed to the central core using hook and loop fasteners.
 10. The eraser of claim 7, wherein the cleaning sheet, when affixed to the central core, covers the top face, the bottom face, the first end face, the second end face, the front face, and the back face.
 11. The eraser of claim 7, wherein the cleaning sheet, when affixed to the central core, covers the top face, the bottom face, the front face, and the back face.
 12. The eraser of claim 7, wherein the cleaning sheet, when affixed to the central core, covers the bottom face, the first end face, the second end face, the front face, and the back face.
 13. The eraser of claim 7, wherein the cleaning sheet, when affixed to the central core, covers the bottom face, the front face, and the back face.
 14. The eraser of claim 7, wherein the cleaning sheet, when affixed to the central core, covers the bottom face.
 15. A cleaning sheet for cleaning blackboards and whiteboards, wherein the cleaning sheet is a microfiber material.
 16. The cleaning sheet of claim 15, wherein the cleaning sheet is configured to cover six surfaces of a rectangular prism.
 17. The cleaning sheet of claim 15, wherein the cleaning sheet is configured to cover five surfaces of a rectangular prism.
 18. The cleaning sheet of claim 15, wherein the cleaning sheet is configured to cover four contiguous surfaces of a rectangular prism.
 19. The cleaning sheet of claim 15, wherein the cleaning sheet is configured to cover three contiguous surfaces of a rectangular prism.
 20. The cleaning sheet of claim 15, wherein the cleaning sheet is configured to cover one surface of a rectangular prism. 